Improved lamp-chimney



E. L E. D. DITHRIDGE. Lmp Chimney. No.` 33,428. Patented Oct. 8, 1861.

Wns'ses: Inventory:

MJ@ @M ge/7% v scription thereof, reference being had to the UNITED STATES PATENTV GEEICE.

EDVARD DITHRIDGE AND EDWARD D. DITHRIDGE, OF PITTSBURG,

' PENNSYLVANIA.

IMPRovED LAMP-CHIMNEY.

Specication forming part of Letters Patent No. 33,428, dated October 8, 1861.

To all whom it may concern:

Be it known that We, EDWARD DITHRIDGE and EDWARD D. DITHRIDGE, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and Improved Chimney for Lamps; and we do hereby declare that the following is a full and exact deaccompanying drawings, and to the letters of reference marked thereon.

The nature of ourinven tion consists in mak'- ing a lamp-chimney with a round base and top andan oval-shaped bulge for the purpose of adaptingit to the ordinary round mounting of lamps in which fiat wicks are used, and also for bringing the air equally in contact with the blaze.

To enable others skilled in the art to make and use our invention, we will proceed to describe its construction and operation.

In the laccompanying' drawings, Figure lis a perspective'view in outline of the chimney. Fig. 2 is a cut or sectional view and represents the oval shape of the bulge of chimney, and also represents the wick-holder and its relative position to the chimney. Fig. 3 is a cut or sectional view of the bulge of the old and well-known form of chimney for lamps in which iiat wicks are used.

a is the chimney.

b is the wick-holder.

c is the space for the wick.

y The advantages of our improvement are as follows:

First. The space between the blaze and wick of the lamp and the sides of the chimney being equally divided by means of 'the ovalshaped bulge, the air is evenly distributed around the wick and blaze. Thus all liability of the chimney becoming smoked is avoided.

Second. The oval shape of the bulge will allow the thimney to expand suddenly without liability of cracking. It willbe observed that the ordinary chimney with the round bulge when suddenly heated is very liable to crack, the expansion having to follow the circle, and glass not being of a pliant nature, it must of necessity crack when suddenly heated. Now the only way to obviate the cracking of the chimney is to make the bulge oval-shaped, which will allow the two Hat sides of the bulge to vibrate and thus relieve the chimney from all strain caused by expansion.

Third. The equal distribution and uniform action of the air on the wick and blaze caused by the oval-shaped bulge will givealarger and brighter light than can be obtained by the use of the round bulge in the ordinary chimney.

Fourth. By the use of the round base when used in connection with the oval-shaped bulge all grinding and fitting are avoided, thereby saving greatly in the cost of manufacture.

Fifth. The round base when used in connection with the oval-shaped bulge adapts the chimney to the ordinary round mounting of lamps which are now in general use.

Sixth. The chimney is not liable to be broken by accident caused by rolling. Hence it will not require so much care in handling.

We are aware that lamp-shades have been made of an oval shape having an oval base. Therefore We do not claim, broadly, the use of the oval shape or formed lamp chimney or shades; but

What we do claim is- A new article of manufacture, consisting of a lamp-chimney with a round base and top and an oval-shaped bulge, arranged and constructed as herein described, for the purpose set forth.

EDVD. DITHRIDGE. EDlVARD D. DITHRIDGE.

Witnesses:

H. I. Roenes, JAMES J. JOHNSTON. 

